On October 24th, 2015 I was invited to give a talk at the Swedish astronomy day (“Astronomdagarna“) in Uppsala. You can find the video stream of my presentation below. I talk about the impact of light pollution on wildlife, ecosystem, human health and well-being and further show how light pollution can be minimized. I present zenithal night sky brightness measurements performed in Stockholm using a Sky Quality Meter and discuss a first analysis of the data, including influence of different environmental conditions, the circalunar rhythm and how auroral activity can alter the nightsky brightness level. Finally, the results are compared to similar measurements performed in Berlin and Vienna.